More than 60% of people living in Angola’s 305 rural villages across eight provinces suffer from onchocerciasis, or River Blindness, a disease causing serious visual impairment, a study conducted in that country between February and August this year has found.
The research, jointly conducted by the World Health Organisation and the Angolan government, revealed that the condition is caused by Onchocerca volvulus — a parasitic worm transmitted into human hosts by the black fly (Simulium damnosum) — and presenting various debilitating symptoms including serious visual impairment (often blindness), rashes, skin lesions, intense itching and de-pigmentation of the skin, and lymphadenitis.
Medical news organisation Med Info director, Doctor Stephen Toovey, on Wednesday quoted the African Programme for Onchocerciasis Control (Apoc), which conducted the research, as saying the Angolan health ministry and the health authorities in the provinces covered by the study were ”alarmed” at the results, as onchocerciasis was previously almost unknown in those parts of Angola.
”Moreover, Apoc has made good progress in reducing the incidence and severity of the disease in 17 African countries, including Angola, since its inception in 1995.
”Apoc’s primary objective is to treat onchocerciasis patients with ivermectin, a drug that kills the pre-larval stage of Onchocerca volvulus that is responsible for the debilitating symptoms of onchocerciasis,” he said.
Toovey said the drug also contributed in reduced disease transmission. As a secondary measure, the organisation was aiming to interrupt the disease’s transmission by eliminating the black fly in a few isolated foci through the application of insecticides to the breeding sites of Simulium damnosum.
The apparent re-emergence of onchocerciasis in the regions studied, together with the possibility that dispersed cases in other villages have been overlooked, had prompted the formulation of a high priority action plan for all of Angola.
The plan would add momentum to Apoc’s activities by mass-treating the population with ivermectin.
How does the relatively high incidence of onchocerciasis impact on travellers to Angola?
Quoting research studies, Dr Andrew Jamieson, SA Airways-Netcare Travel Clinics medical director, said visitors to areas where onchocerciasis was endemic for less than three months appeared to be at low risk of infestation.
Temporary residents and others who visit the endemic regions for longer periods and who live or work near black fly habitats were, however, at greater risk.
”Travellers to Angola should avoid riverside areas as these are typical black fly habitats.
”They should also take personal protective measures, such as wearing clothes that cover as much of the body as possible and using insecticides on clothing, shoes, bedding and other gear,” he said.
Although there is no vaccine and no effective chemo-prophylaxis for onchocerciasis, Dr Jamieson encouraged travellers who plan to visit endemic areas to consult with a specialist in infectious diseases or tropical medicine.
”The personnel at the SAA-Netcare Travel Clinics around South Africa are well versed in these subjects.
”They are also fully aware of the travel-health status of countries in Africa and around the world and can advise regarding outbreaks, new developments, applicable vaccination requirements, precautionary measures and so on.” – Sapa